Individuals who need more protein in their diets should take protein powder either as a replacement for a meal or as a snack. People with healthy diets usually do not need to take protein powder.
Protein powder is effective for people experiencing growth spurts, starting a muscle-building program, working out or training more, or dramatically changing their diets. Protein powder is useful for teenagers whose bodies are using more protein and vegans whose bodies no longer take in the protein commonly found in fish, meat, cheese, milk and chicken. The powder can also be taken by athletes who have suffered injuries and want to assist the body's natural healing process.
The three most common types of protein powders are casein, whey and soy. Whey is a commonly used milk protein that offers the advantages of a complete protein where soy protein is often preferred by vegans. Whey is more water-soluble than soy protein, and some find the taste of soy protein to be unpleasant as compared to whey protein.
Different types of protein powder also vary in regards to price. Casual athletes who aren't focused on a specific area of improvement are usually better off with a more affordable protein powder.